The effect of intrathecal and epidural narcotic analgesia on the length of labor.

A number of studies have shown conflicting results on the effect of epidural (EPI) analgesia on the length of labor. Combined spinal-epidural (CSE) and intrathecal analgesia (ITA) techniques have been used to provide pain relief for parturients, but currently there are few studies comparing EPI, CSE, and ITA techniques and their effect on the length of labor. Intrathecal opioids provide immediate pain relief for the parturient without autonomic, sensory, or motor blockade. The purpose of this retrospective study is to identify the effects of ITA on the length of labor compared with other regional anesthesia techniques. A total of 213 uncomplicated obstetric charts were reviewed in a 70-bed Air Force hospital that provided EPI, CSE, and ITA for obstetrical patients. The study consisted of the following four groups: (1) CSE (n = 76), (2) EPI(n = 41), (3) ITA (n = 49), and (4) no regional analgesia (NR) (n = 47). The results showed that the length of first-stage labor was statistically significantly less for those who received ITA compared with those who received CSE, EPI, and NR (P < .001). Second-stage labor was statistically significantly shorter for the NR group compared with the CSE and EPI groups (P < .01). No statistically significant difference was found between the length of second stage for ITA and NR groups. ITA analgesia shortened the first stage significantly in both primipara and multipara patients (P < .01). These results imply that the use of intrathecal opioids in the obstetrical patient does not prolong labor and seems to shorten the first stage of labor in both the primipara and multipara patients.